Science shows that drunk people don’t know how drunk they are

We now have solid scientific evidence
that people are completely unable to determine how soused they are when
drinking with a group. A team of social scientists recently completed a
study of bar and club hoppers in Cardiff, Wales and discovered that
most had incredibly inaccurate notions of their drunkenness and the
dangers of drinking. But the researchers also learned something
non-obvious and intriguing about how people estimate their levels of inebriation.

In a BMC Public Health paper,
the researchers write that they wanted to know "how people judge their
drunkenness and the health consequences of their drinking whilst they
are intoxicated in social drinking environments." So they spent several
months going to four different party neighborhoods in Cardiff between
8pm and 3am on Friday and Saturday nights. These neighborhoods had, as
the researchers put it, "a high density of premises licensed for the
on-site sale and consumption of alcohol." To get a broad sample of bar
hoppers, researchers would approach every seventh person they saw and
ask them to participate in the survey. The idea was to try to get people
who were out with different social groups, because the researchers were
interested in how peers influenced people's subjective experience of
drunkenness.

Once a Cardiff drinker agreed to participate,
the researchers would administer a blood alcohol test to determine their
actual level of inebriation. Then they would ask the drinker a series
of four questions:

1) How drunk are you right now, on a 1 (totally sober) to 10 (completely drunk) scale?

2) How extreme has your drinking been tonight, on a 1 (not at all) to 10 (completely extreme) scale?”

3) If you drank as much as you have tonight
every week, how likely is it that you will damage your health in the
next 15 years, on a 1 (definitely will not) to 10 (definitely will)
scale?

4) If you drank as much as you have tonight
every week how likely is it that you will get cirrhosis of the liver in
the next 15 years, on a 1 (definitely will not) to 10 (definitely will)
scale?

As amusing as it is to imagine clubbers being
accosted by scientists at 2am with this list of vaguely terrifying
questions, the results were anything but a joke. By comparing subjective
reports of drunkenness with actual blood alcohol test results, the
researchers discerned that people were measuring their drunkenness and
health risks on a ranked scale. "People in drinking environments make
decisions to drink more on the basis of their observation of people
around them," they write.

The researchers speculate that this odd
phenomenon could actually be part of humanity's evolutionary
predilection for thinking in terms of rank. "Such rank sensitivity may
also explain why drinking increases in a society; if everyone drank
another 10 units per week, no one would believe themselves to be more at
risk of alcohol-related disorder, as their rank positions would remain
the same," they write. Put simply, people judged how drunk they were in
relation to their peer group. If everyone around him was blackout drunk,
an extremely inebriated person would consider himself relatively sober.
But by the same token, a tipsy person with sober people was quite
conscious of being loaded.

After a rigorous statistical analysis, the
researchers found that people were basing their rank sensitivity not on
the drunkest people around them but on the most sober. "It appears that
drinkers are more self-aware of their own level of intoxication when in
the presence of those who are sober," they conclude. As a result,
we might be able to curb dangerous drinking just by encouraging the
presence of "sober ambassadors" like designated drivers in bars and
clubs. Our social groups determine how much we drink, but they often
nudge us in a healthier direction more than we realize.

Cardiff University social scientist Simon
Moore, an author on the study, remarked in a release that "we could
either work to reduce the number of very drunk people in a drinking
environment, or we could increase the number of people who are sober.
Our theory predicts the latter approach would have greatest impact."